Farmer John is planning to build \(N\) (\(1 \leq N \leq 10^5\)) farms that will be
connected by \(N-1\) roads, forming a tree (i.e., all farms are reachable from
each-other, and there are no cycles). Each farm contains a cow, whose breed is
either Guernsey or Holstein.

Farmer John's \(M\) friends (\(1 \leq M \leq 10^5\)) often come to visit him. During
a visit with friend \(i\), Farmer John will walk with his friend along the unique
path of roads from farm \(A_i\) to farm \(B_i\) (it may be the case that
\(A_i = B_i\)). Additionally, they can try some milk from any cow along the path
they walk. Since most of Farmer John's friends are also farmers, they have very
strong preferences regarding milk. Some of his friends will only drink Guernsey
milk, while the remainder will only drink Holstein milk. Any of Farmer John's
friends will only be happy if they can drink their preferred type of milk during
their visit.

Please determine whether each friend will be happy after visiting.

Problem credits: Spencer Compton

SCORING

• Test cases 2-5 satisfy \(N\le 10^3, M\le 2\cdot 10^3.\)

Problem credits: Spencer Compton

The first line contains the two integers \(N\) and \(M\).

The second line contains a string of length \(N\). The \(i\)th character of the
string is 'G' if the cow in the \(i\)th farm is a Guernsey, or 'H' if the cow in
the \(i\)th farm is a Holstein.

The next \(N-1\) lines each contain two distinct integers \(X\) and \(Y\)
(\(1 \leq X, Y \leq N\)), indicating that there is a road between farms \(X\) and
\(Y\).

The next \(M\) lines contain integers \(A_i\), \(B_i\), and a character \(C_i\). \(A_i\)
and \(B_i\) represent the endpoints of the path walked during friend \(i\)'s visit,
while \(C_i\) is either G or H if the \(i\)th friend prefers Guernsey milk or
Holstein milk.

Print a binary string of length \(M\). The \(i\)th character of the string should be
'1' if the \(i\)th friend will be happy, or '0' otherwise.

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